The Stovebolt Site Forums The Shop Area Engine Shop Hydraulic or solid lifters

Fellow Bolters, I have this engine in my 2nd series '55.

Casting #3769716 (1958-62 235)
Casting date CON 4 E31 (May 03, 1961)
Serial #F 0504 JC (Triftmaster 235 with 3 sp trans)

Thanks to the people on this site for all the information to decode these numbers. Right now the engine has hydraulic lifters in it. Based on the JC suffix in the serial number this is a truck engine and as such should it have solid lifters?

The spec guide (Std Catalog of Chevrolet Truck) and the shop manual disagree on this. The guide says hydraulic, the manual says solids. since the later 235s are drilled for either type, it is entirely posible that the hydraulic cam is factory, possibly due to a parts shortage or midyear change. You can put a solid lifter cam in it, though.

Thanks Bill. Seems like the more I learn, the more there is to learn. The reason I post this question is I have never been happy with the valve adjustment on this engine compared to the "smooth as a sewing machine" quality of my other truck. They never seem to quiet down even though I adjust them based on information found on this site and the shop manual. What if I have a solid camshaft with the hydraulic valves?

Lifters and distributors (gears) should always match the cam.
Later cams, lifters and distributors are made from different metal than earlier ones. Any mismatch and premature wear can occur.
It's possible that your engine was rebuilt at least once and you can't always be sure what cam and if the correct matching lifters and distributor were used.

There is a way how to identify early solid and hydraulic cams, by looking at them with the oil pan removed.
Not sure if the same method can be used to identify later already installed solid and hydraulic cams.

Hydraulic lifters on a solid cam are less of a problem than the other way around.
Solid cams have gradually raising and lowering 'ramps' to ease the cam lobes against the lifters and their valve lash.
Hydraulic cams have a much faster valve lift than solids.

Hydraulic lifters need to be replaced eventually, as old and worn ones can collapse and cause a lot of noise at the rockers and lose power.
If you tightened them to spec (1-1/2 turn after clicking stops) and you still get valve lash clicking, it's best to replace them.

On the road, you are reading between the lines here. The engine has a placard indicating a rebuild somewhere along the way (but before I got the engine). I have seen specs for tightening hydraulic lifters 3/4 turn after clicking stops but this is from a 55 shop manual. I will next try the 1 1/2 turns and look into new lifters. Thanks so much.

I usually get ignored or flamed when I start offering advice about cams and lifters, but here I go again- - - - - -

Mixing hydraulic and solid cams and lifters is never a good idea. There are just too many fundamental design differences to overcome. If a cam or a set of lifters needs replacement, replace them both. Lifters have a tendency to wear into a cup shape on the bottom, which wears out the cam lobes as well. Install a new cam and matching lifters, either solid or hydraulic, break it in properly, and do a correct adjustment. It should last tens of thousands of miles, usually 100K or more. I prefer hydraulics, but that's a personal opinion, not a set-in-stone fact.
Jerry

Has anyone had trouble using the newer oils in their engines?? I've heard varing stories of some having trouble with fast wear on cams ect.... because of the zinc being removed from newer motor oils. John

search the forum on ZDDP

Lots of places are selling the ZDDP additive. Try Kirban.com and/or Eastwood sell it.

Hi Jerry,

No flaming or ignoring here. In fact I've read tons of your posts in the archives. They are very knowledgable and well thought out.

Is there a way (short of pulling the camshaft) to know if I have matching cam and lifters?

I just found some info, I compiled a while back....

Later cams starting with 1954 powerglide and all later years used cast alloy iron cams versus older cams made from forged steel.
You can identify hydraulic from solid cams by finding the casting lumps, leftover from the casting process.

They are located on the rear of the cam between the 3rd and 2nd to the rearmost cam lobes.
2 or 4 raised lumps identify it as a hydraulic cam.
1 or 3 raised lumps make it a solid lifter cam.

No need to disassemble anything, just drop the pan and turn the engine until you see the lumps...

The later lifter designs were different from the earlier ones and don't interchange.
So if you identify a hydraulic cam you are good and just have to check what year your distributor is.
Part number can be found when removing the cap.


A few years ago, when I started overhauling my old 235, I knew little about cams and lifters.
I had some collapsed hydraulic lifters and just replaced all of them with a complete NOS set I found cheaply.
Pushrods turned freely and power increased slightly.
I still drive it daily ever since with no issues so far.
Maybe just luck, but the stock valve spring pressures are pretty low on these engines.

The problem is, good hydraulic lifters are harder to find these days and can be expensive.
Once you installed and broken them in on the old cam, you can't reuse them on a fresh cam, should something go wrong.
Although there are still cam grinders who recondition rare obsolete lifters and the critical convex hardened bottom surface.

On the road,

That's the million dollar information you just can't get anywhere else than right here! Thanks so much.

On the road,

Dropped the pan today and found 2 raised lumps in between the 2nd and 3rd cam lobes. The lumps looked like poorly stamped 6's or 9's. On the other side of the camshaft in this same area was a slightly smooth section with a set of 3 stamped numbers (736).

Between the 3rd and 4th cam lobes I found what I would consider the casting date of C31 (March 3, 1961). This number had the characteristic round head screw in front and flat head screw toward the rear. Many thanks.

Also checked out your website and truck. Delux all the way.